Dental cement.



UNITED STATES PATENT OFFICE.

' WALTER s. caownrm, or: rnrnannnrnm, WHITE DENTAL MANUFACTURING comravr, A conrona rron or rmmsrnvnnm.

ments in Dental Cements, of-whichthe fol PENNSYLVANJ IA, ASSIG-NOR TOTHE S. S.

DENTAL CEMENT.

No Drawing.

To all whom it may concern:

Be it known that I, WALTER S. Gnownnn, a citizen of the United States,and aresident of the city of Philadelphia, county of Philadelphia,"State of Pennsylvania, have invented certain new and usefulImprovelowing is a specification. v

' My nvention relates particularly to cements adapted to be used in theart of dentistry, and, is especially'directed to that class of cementswhich are employed in stoppingor filling cavitiesof natural teeth, andfor setting crowns, bridges and inlays;

; The principal object of my invention.is,-

to provide a cement that exhibits the characteristic germicidal actionof mercury salts in a mild and controllable manner.

i Other obj ects of my invention are, to provide a cement that will bemore. germicidalin its action than any of the well known copper cementsnow used in, dentistry, and that may be used in the month without dangerof the poisonous action of aqueous solutions of mercury salts. 4

My .invention comprehends a cement powder which when colnpounded with asuitable liquid to a mass of proper consistency for the purpose, andallowed to set,

will manifest germicidal action upon its surroundings so as to inhibitthe recurrence of dental carieson decay of the teeth.

I have found that a desirable composi- I tion which exhibits thecharacteristic germicidal action of mercury in a mild andcontrollable'manner. ma be preferably contained in composition with anordinary oxyphosphate of zinc cement powder, a phosphate oflmercurycompound. Furthermore, I have found that by mixone per cent.- ofmercuryv phosphate with, cement powder, and mixing the resultant powderwith cement liquid, on setting, a mass results which is germicidal to asuflicient extent to prevent or' inhibit the growth of bacteria in itsimmediate environments, and that the physical'properties of the. cementare not impared thereby.

Specification of Letters Patent.

Patented 0a. 23, 1917.

Application filed January 26, 1917. Serial No. 144,617.

The presence of mercury salt causes the cement to be more germicidal inits action than any of the copper cements now em:

ployed in dentistry, yet it may be usedin the mouth without danger ofthe poisonous action of aqueous solutions of mercury salts.

' employed to produce the result desired, and

that the result may be produced if the mercury salt be dissolved in thecement liquid in such .quantity that the hardened cement contain anequal proportion ofmercury-to that produced from the admixture ofmercury salt with the cement powder; and, therefore, I do not desire tolimit my invention to the precise proportions and order of mixing hereinset forth and de-' 7 fined'in the appended claims.

Having thus described my invention, I claim:

1'. An article of manufacture comprising a filling cement having, incomposition,

cement powder and a phosphate of mercury.

. '2. An article of manufacture comprising a filling cement having, incomposition,

oxyphosphate of zinc cement powder anda phosphate of mercury.

' 3. An article of manufacture comprising a filling cement containing aslightly soluble mercury compound, and adapted to un-' dergo a settingreaction when compounded with a phosphoric acid solution.

4:. An article of manufacture comprising the mixture of an oxyphosphateof zinc cement powder and an acid phosphate liquid containing dissolvedin it a mercury salt. 1 a

In witness whereof, I have hereunto set .my7hand this 25th day ofJanuary, A. D., 191

WALTER s. oRoWELL.

Witnesses v 'WmmAM- J. RUSSELL,

Cameron 0.

so i

